Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 17: Problem 29

Predict the sign of \(\Delta S_{\text {surr }}\) for the following processes. a. \(\mathrm{H}_{2} \mathrm{O}(l) \longrightarrow \mathrm{H}_{2} \mathrm{O}(g)\) b. \(I_{2}(g) \longrightarrow I_{2}(s)\)

Short Answer

Expert verified
a. For the process \(H_2O(l) \longrightarrow H_2O(g)\), \(\Delta S_{\text{surr}} < 0\). b. For the process \(I_2(g) \longrightarrow I_2(s)\), \(\Delta S_{\text{surr}} > 0\).

Step by step solution

01

Process a: \(H_2O(l) \longrightarrow H_2O(g)\)

This process involves the conversion of water from liquid state to gaseous state. When water evaporates, it absorbs heat from the surroundings, causing the surroundings to cool down. As heat flows out of the surroundings, the entropy of the surroundings decreases. Therefore, for this process, \(\Delta S_{\text{surr}}\) is negative.
02

Process b: \(I_2(g) \longrightarrow I_2(s)\)

This process involves the conversion of iodine from gaseous state to solid state. When iodine undergoes this change, it releases heat to the surroundings, causing the surroundings to warm up. As heat flows into the surroundings, the entropy of the surroundings increases. Therefore, for this process, \(\Delta S_{\text{surr}}\) is positive. To summarize: a. \(\Delta S_{\text{surr}} < 0\) for the process \(H_2O(l) \longrightarrow H_2O(g)\) b. \(\Delta S_{\text{surr}} > 0\) for the process \(I_2(g) \longrightarrow I_2(s)\)

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Entropy has been described as "time's arrow." Interpret this view of entropy.

Consider the following reaction: \(\mathrm{H}_{2} \mathrm{O}(g)+\mathrm{Cl}_{2} \mathrm{O}(g) \rightleftharpoons 2 \mathrm{HOCl}(g) \quad K_{298}=0.090\) For \(\mathrm{Cl}_{2} \mathrm{O}(g)\), \(\Delta G_{\mathrm{f}}^{\circ}=97.9 \mathrm{~kJ} / \mathrm{mol}\) \(\Delta H_{\mathrm{f}}^{\circ}=80.3 \mathrm{~kJ} / \mathrm{mol}\) \(S^{\circ}=266.1 \mathrm{~J} / \mathrm{K} \cdot \mathrm{mol}\) a. Calculate \(\Delta G^{\circ}\) for the reaction using the equation \(\Delta G^{\circ}=\) \(-R T \ln (K)\) b. Use bond energy values (Table 8.4) to estimate \(\Delta H^{\circ}\) for the reaction. c. Use the results from parts a and \(b\) to estimate \(\Delta S^{\circ}\) for the reaction. d. Estimate \(\Delta H_{\mathrm{f}}^{\circ}\) and \(S^{\circ}\) for \(\mathrm{HOCl}(g)\). e. Estimate the value of \(K\) at \(500 . \mathrm{K}\). f. Calculate \(\Delta G\) at \(25^{\circ} \mathrm{C}\) when \(P_{\mathrm{H}_{2} \mathrm{O}}=18\) torr, \(P_{\mathrm{Cl}_{2} \mathrm{O}}=2.0\) torr, and \(P_{\mathrm{HOCl}}=0.10\) torr.

The third law of thermodynamics states that the entropy of a perfect crystal at \(0 \mathrm{~K}\) is zero. In Appendix \(4, \mathrm{~F}^{-}(a q), \mathrm{OH}^{-}(a q)\), and \(\mathrm{S}^{2-}(a q)\) all have negative standard entropy values. How can \(S^{\circ}\) values be less than zero?

Hydrogen sulfide can be removed from natural gas by the reaction $$2 \mathrm{H}_{2} \mathrm{~S}(g)+\mathrm{SO}_{2}(g) \rightleftharpoons 3 \mathrm{~S}(s)+2 \mathrm{H}_{2} \mathrm{O}(g)$$ Calculate \(\Delta G^{\circ}\) and \(K\) (at \(298 \mathrm{~K}\) ) for this reaction. Would this reaction be favored at a high or low temperature?

Predict the sign of \(\Delta S^{\circ}\) for each of the following changes. a. \(\mathrm{Na}(s)+\frac{1}{2} \mathrm{Cl}_{2}(g) \longrightarrow \mathrm{NaCl}(s)\) b. \(\mathrm{N}_{2}(\mathrm{~g})+3 \mathrm{H}_{2}(\mathrm{~g}) \longrightarrow 2 \mathrm{NH}_{3}(\mathrm{~g})\) c. \(\mathrm{NaCl}(s) \longrightarrow \mathrm{Na}^{+}(a q)+\mathrm{Cl}^{-}(a q)\) d. \(\mathrm{NaCl}(s) \longrightarrow \mathrm{NaCl}(l)\)
See all solutions

Recommended explanations on Chemistry Textbooks

Making Measurements

Read Explanation

The Earths Atmosphere

Read Explanation

Physical Chemistry

Read Explanation

Chemistry Branches

Read Explanation

Kinetics

Read Explanation

Inorganic Chemistry

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free